Auralex GRAMMA

On [this page](http://www.auralex.com/auralex-user/joe-bonamassa/) of Auralex's website, it quotes Joe Bonamassa saying, “I use Auralex Great GRAMMAS™, which are carefully engineered isolation risers that the amps sit on. You put your 4x12s on them to decouple them from the stage. You don’t get the rumble from the stage, which is sometimes hollow, sometimes not. It varies every day. The Great GRAMMAs™ make it much more consistent by taking the stage out of the equation.”